1. Field of the Invention
The present invention relates to a skin-cosmetic composition useful for preventing the skin from being roughened, chapped or cracked, or from aging.
2. Prior Art of the Invention
Heretofore, various cell activation promoters, such as hyaluronic acid, allantoin and its derivatives, deprotenized bovine blood, extracts from lithospermum roots, extracts from ginsengs, extracts from placentae (various materials extracted from natural substances such as proteins, polysaccharides, extracts:, natural polymers, etc.), etc., have been incorporated into skin-cosmetic materials to be applied to the skin to cure cuts, burns, scalds, etc., for preventing the skin from being chapped, cracked, inflamed or aged, for preventing hemorrhoids, for promoting cell activation in the skin, and for accelerating the healing of wounds on the skin.
However, agents for external use in skin containing theses ingredients having efficacy were not sufficiently effective for the above-mentioned objects, and therefore skin-cosmetic composition having a significantly satisfactory cell-activating effect have heretofore been desirable.
Under the above-mentioned circumstances, the present inventors have assiduously studied to obtain a novel skin-cosmetic composition and have found that compounds of a formula (I): ##STR2## wherein R.sup.1 represents an alkyl group having 1 to 10 carbon atoms; R.sup.2 represents an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or cycloalkyl group having 3 to 7 carbon atoms; and X represents --O-- or --NH--, which are known to be efficacious as pharmaceutical compositions for controlling liver damage of humans and animals in U.S. Pat. No. 4,118,506 and are known to be efficacious as wound healing accelerators in GB-A-2263234 and AU-B-31828/93, have a cell activation promoting effect and are therefore efficacious as "skin-" cosmetic materials for preventing the skin from being roughened, chapped or cracked, or from aging. On the basis of this finding, the present invention has been completed.